1. Field of the Invention
This invention relates to a new and improved system for coordinating aircraft and selective areas on the ground, and more particularly, to a radio control system utilizing selectively and sequentially activated lights or other visual aids to control crop dusting operations. In a preferred embodiment of the invention, a radio transmitter is placed in an aircraft adapted for crop dusting, and a receiver equipped with an antenna is located on the ground with a series of lights or other visual aids located in selected positions in the field or area to be treated. The aircraft then makes a series of passes over the lights or alternative visual aids, and with each pass, causes one of the lights or visual aids to be activated by means of the transmitter, thereby precisely positioning the aircraft with respect to selected areas of the field.
2. Description of the Prior Art
Heretofore, air-to-ground operations such as crop dusting and simulated bombing or strafing runs have been achieved principally by means of flagging operations whereby the aircraft is guided in its passes over the field by a person standing in the field and signaling the desired path of flight with flags. Alternatively, visual aids such as signs are sometimes placed in strategic locations in the field to guide the pilot in successive passes over the field. In the case of crop dusting, the use of a flagman is a potentially hazardous operation since many of the chemicals utilized in the dusting operation are harmful to human beings and the aircraft must fly directly over the flagman at very low altitudes. Accordingly, the flagman must be clothed with a hood and protective clothing in order to minimize the amount of spray or poison which contacts the skin and must always be alert, since he is constantly in the flight path of the aircraft. Even under ideal circumstances where the flagman is properly clothed, periodic blood tests must be run in order to ascertain the level of toxic chemicals which the body has ingested as a result of the crop dusting operation, and the individual must be periodically removed from contact with the chemicals to insure his safety.
In the case of fixed signs of visual aids which guide the pilot on successive passes over the field, such signs are frequently difficult to read, and where large fields must be treated, it is frequently difficult to ascertain which sign was used by the pilot as the previous reference point in the dusting operation. This difficulty frequently results in excessive dusting of certain areas of the field and little or no dusting of other areas. Furthermore, the pilot's concentration on such a visual aid may cause him to lose control of the aircraft in a turn or other maneuver, thereby presenting a hazard to both pilot and aircraft.
Accordingly, an object of this invention is to provide an improved system for use in crop dusting and other air-to-ground operations where visual reference is necessary for coordination between an aircraft and specified areas of the ground, which system automatically guides the pilot through sequential passes over such specified areas.
Another object of this invention is to provide an improved crop dusting operation which permits uniform air-to-ground treatment of the field in question, including the dissemination of seeds and powdered and liquid chemicals.
Yet another object of this invention is to provide an improved system for guiding an aircraft over specified areas of a field in crop dusting operations, which includes the use of selectively energized lights or other visual aids activated by the aircraft in successive passes over the field.
A still further object of the invention is to provide an improved ground position indicator system for effecting uniform air-to-ground treatment of crops in crop dusting operations which includes activation of visual aids located on the ground to guide an aircraft in successive passes over the crops, which activation is initiated by a transmitter located in the aircraft or in a location on the ground at a safe distance from the field.
A still further object of the invention is to provide a ground position indicator system which is capable of being activated from an aircraft to selectively treat a field of crops from the air by effecting sequential and selective activation of a series of lights positioned in the field at selected intervals, thereby enabling the pilot to uniformly treat the field.
Yet another object of the invention is to provide a ground position indicator system for crop dusting which utilizes a portable visual aid arrangement capable of being located in substantially any area of a field for guiding an aircraft.